Combined range-finder and turret.



Patented Nov. 20, I900.

B. A. FISKE. COMBINED RANGE FINDER AND TURRET.

(Appliratidn filed June 28, 1900.)

2 Sheets-Sheet I.

(,No Model.)

Invegtqir flaw m 42M Attys.

n. vv :2. TNE NORRYS PETERS co. woraumo wASruNm'o No. 66l,968. PatentedNov. 20, I900. B. A. FISKE. COMBINED RANGE FINDER AND TU RRET.

(Application filed June 28,1900?) 2 Sheets-Sheet 2.

'(No Model.)

Witnesses Attys.

TNL NORRIS PETER cov Pnmuuma. WASHINGTON, n c.

llnrrso STATES FATENT QFMQEO BRADLEY'ALLAN FISKE, OF NEW YORK, N. Y.-

COIVIBINED RANGE-FINDER AND TURRET.

SPECIFICATION forming part of Letters Patent No. 661,968, dated November20, 1900.

Application filed June 28, 1900. .Serial No. 21,869. \No model-F Myinvention relates to a combined rangefinder and turret, the turretsupporting and offering protection to the range-finder and by itsrotation directing the observing device of the range-finder toward thetarget. The range-finder which is combined with the turret may be of anydesiredoptical type wherein the range is ascertained by a determinationof the angles of a known base-line with re spect to the target. Theserange-finders at the present time are divided into two general classes,the first employing a single telescope arranged at one end of the knownbase-line and through which the target is observed directly and areflector at the other end of the base-line by which rays from thetarget are reflected to a second reflector carried by the telescopeimmediately in front of its objectglass, so that by properly adjustingthe first reflector the direct and reflected rays entering the objectiveof the telescope may be vertically alined. Obviously the extent ofadjustment required to aline the two images determines the angle at theobject which the known base-line subtends, so that by properlygraduating the adjusting mechanism the range or distance of the objectcan be immediately ascertained. In the second class of range-finders areflector is employed at each end of the base-line, the telescope beinggenerally centrally mounted with respect to the same and receivingreflected images of the target from both reflectors. Any convenientarrangement, such as a prism or other optical devices for suitablyretracting the rays, is employed, whereby the two images may be alined,the position to which said refracting devices require to be moved toaline the images offering a basis for an immediate calculation of thedistance of the object.

Up to the present time range-finders of the class referred to have notproved entirely practicable, for the reason that owing to the smallbase-line used-2'. 6., the distance separating the tworeflecting-surfaces-the angle between the two rays is small andconsiderable magnification is required, resulting in loss of light andgreat vibration of the reflected images unless the ship and platform beabsolutely steady. Furthermore, the shortness of the base-line employedresults in only a slight angle between the two rays, so that opportunityfor error is present. Up to the present time the provision of a longbase-line has not been possible with instruments of this type owing tolack of deck-space on shipboard. Aside from the optical difficultiesreferred to, the use of these range-finders for naval purposes has beenobjectionable, for the reason that in order to protect them from theblast and concussion of the heavy guns they have had to be employedabove deck, generally in the fighting-top, and therefore unnecessarilyexposing the operators to the fire of the enemy.

By means of my present invention the difficulties referred to areentirely overcome, as I am enabled to use a long base-line, while at thesame time the apparatus itself is not only protected from the effect ofthe guns, both of the enemy and of the ship on which it is used, but theoperator is absolutely safe and can handle the instrument withsteadiness and coolness.

Briefly stated, myinvention consists in combining an opticalrange-finder with a revolving turret, either of a vessel or of a landfortif fication, in such a way that the turret forms the support for theinstrument, revolves it to the proper position for observing the target,and effectively protects both the instrument and the operator from theeffect of shot and shell.

In order that my invention may be better understood, attention isdirected to the accompanying drawings, forming part of thisspecification, in which- I Figure 1 is a diagram illustrating theoperation of range-finders of the first-class above referred to, whereinthe telescope is mounted at one end of the base-line; and 2, acorresponding view illustrating the operation of range-finders of thesecond-class, wherein the telescope is centrally arranged with re spectto the base-line and a reflector is employed at each end of thebase-line. Fig. 3

is a vertical sectional view through a ships turret, showing thepreferred embodiment of my invention applied thereto; Fig. 4, a sectiontaken at right angles to Fig. 3; Fig. 5, a plan view with theprotecting-armor for the device removed, and Fig. 6 a section on theline 6 6 of Fig. 3.

In all of the above views corresponding parts are represented by thesame letters and numerals of reference.

Before referring to the mechanical construction of my improved devicethe general construction and operation of the optical rangefinders ofthe type which I prefer to employ may be explained.

In Fig. 1, a represents a telescope having a large object-glass andwhich is trained directly upon the target, the direct rays beingrepresented by the line b. A reflector 0, generally in the form of aprism, is carried on the base which supports the telescope and receivesthe direct rays d from the target. The rays (1 are reflected at e to areflector f, so that a reflected image of the target will be alsoprojected through the object-glass. The distance separating thereflecting-surfaces of the reflectors c and f and represented by theline 6 constitutes the known base-line. By shifting the angle of thereflector c the reflected and direct images may be brought intoalinementwithin the objective, and by noting the angle of the reflectorc the range or distance of the object can be immediately ascertained.

In Fig. 2 there are two reflectors g and h at the two ends of thebase-line and two intermediate reflectors t' and j, by which the raysfrom the target may be reflected to the eyepiece of the telescope a,which with this form of device is generally centrally located betweenthe reflectors g and h. The two objectives are located usually betweenthe two systems of reflectors, as shown, and the reflectors i and j, asis well known, are constructed to reinvert the images. Any suitable formof prism, such as 7", or other optical device is used for retracting therays from the target, so that the images projected into the eyepiecewill be brought into alinement, and the position to which the refracting device requires to be moved to eflfect this result.

indicates the range or distance of the target.

I shall describe my improved range-finder as being of the type shown inFig. 1, wherein the telescope a will be located at one side of theturret; but it will be of course obvious that without the exercise ofinvention the improvements may be applied to range-finders of the typeshown in Fig. 2, wherein the telescope will be centrally located withinthe turret or to range-finders of other types.

1 represents a turret, either of a naval vessel or of a landfortification, which is provided with the usual and appropriatemechanism for revolving it, so that the gun or guns therein may bepointed at the target. Pivoted either to the outside or to the insidewalls of the turret are two arms 2 2, which carry a cross-bar 3 at theirupper ends, said cross-bar working as closely to the top of the turretas is practicable. In order to protect the apparatus, an armor-plate 40fthe desired thickness may be secured to the top of the turret, so as toinclose both the cross-bar 3 and the arms 2 2 when the latter arepivoted to the outside of the turret, as shown. Rigidly carried by thecross-bar 3 is a telescope 5, preferably of the type described andclaimed by me in my application for Letters Patent filed May 5, 1900,Serial No. 15,563, and shown more clearly inFig. 6, said telescopehaving two reflecting-surfaces 6 6, arranged as shown, whereby aray oflight entering in the direction indicated by the arrow may be deflectedvertically downward and thence horizontally through an eyepiece 7,whereby the operator within the turret may observe the target outside ofthe same. The objective 8 of the telescope 5 is of a large size, andcarried in front.

thereof is a mirror or prism 9, arranged as shown, whereby direct raysmay enter the objective above or below the prism or mirror 9, whilereflected rays from said prism or mirror may enter the objective aboveor be low the directly-entering rays, as the case .mirror or prism 9 andthence into the telescope. The distance separating thereflecting-surfaces 9 and 11, respectively, is the known base-line ofthe instrument, which obviously is of very much greater length than withthe ordinary range-finders of the type referred to.

In order to properly adjust the reflecting-surface 11 to bring intoalinement the direct and reflected rays entering the objective of thetelescope, I prefer to connect a lever 12 to the pivot 10 and to engagewith said lever a vertically-pivoted adjusting-lever 13, the pivot forwhich is carried ona downwardly-extending arm 14, connected to thecross-bar In order to regulate the position of the adjusting-lever 13,an adjusting-screw 15 may be employed having a suitable scale on itshead, whereby by rotating said adjusting-screw the levers 12 and 13 maybe moved to delicately shift the position of the mirror 11, andtothereby bring into vertical alinement the direct and reflected images ofthe target in the eyepiece of the telescope, as will be understood. Byobservin g the position of the adj listing-screw a visual indication ofthe range will be secured. In order to maintain the object in the fieldof thetelescope as well as in the field of the reflectingsurface 11,notwithstanding the rolling of the vessel on which it may be employed, Iprovide a hand-lever 16, which is connected to the cross-bar 3 and whichworks through a slot 17in the top of the turret, whereby said lever maybe easily grasped by the hand of the operator as he stands observing theobject through the telescope, so that by shifting the position of saidhand-lever the telescope may be maintained in its desired verticality tobe always trained 011 the target, it being obvious, of course, that thehorizontal adjustment of the telescope is effected by the turning of theturret as the guns therein are trained on the object to be hit. It willof course be understood that when the supplemental armort is used forprotecting the range-finder it will be provided with openings 18 thereinopposite to the objective of the telescope and to the reflecting-surface11, and through which openings the target will be observed directly andindirectlyin the operation of the range-finder.

It will be observed that by pivoting the cross-bar 3 on the ends of thearms 2 2 the pivots of said arms are substantially in line with theeyepiece of the telescope and at the height of the eye of anordinary-sized man. Hence the adjustments of the bar to maintain thetelescope trained on the target do not effect a substantial movement ofthe eyepiece of the telescope, which remains, therefore, relativelyfixed in space. This is of great importance in the practical use of theinstrument, for the reason that the operator does not require to keepmoving his head in order to maintain his eye at the eyepiece.

Having now described my invention, what I claim as new, and desire tosecure by Letters Patent, is as follows:

1. The combination with a revolving turret, of an optical ran ge-findercarried thereon and constituting a permanent fixture thereof, wherebythe range-finder will be trained on the target by the rotation of theturret, said range-finder comprising a telescope and two reflectors,said reflectors being secured at approximately the opposite ends of adiameter of the turret, which diameter thereby constitutes the base-lineof the finder, and means for vertically alining the rays which come froma distant object to said opposite ends of the base-line, substantiallyas set forth.

2. The combination witharevolvingturret, of a range-finder carriedthereby and comprising a telescope, the eyepiece of which is out of linewith its objective, and through which the target is observed directly bythe observer within the turret, a reflector mounted opposite saidtelescope and by means of which a reflected image of the object will beobserved through the telescope, and means for alining the direct andreflected rays, substantially as set forth.

3. The combination with a revolving turret, of a range-finder carriedthereby and comprising a telescope the eyepiece of which is out of linewith its objective, said telescope being mounted near one side of theturret and through which the target is observed directly by the observerwithin the turret, a reflector mounted opposite said telescope and bymeans of which a reflected image of the object will be observed throughthe telescope, and means for adjusting the angle of said reflector,substantially as set forth.

at. The combination with a revolving turret, of a cross-bar pivotedthereon, a telescope carried by said bar, through which the target isobserved directly, a reflector carried by the bar diametrically oppositeto the telescope and through which a reflected image of the target isobserved, means for adjusting the angle of said reflector, and means formanually rotating the cross-bar around its pivot, substantially as setforth.

5. The combination with arevolving turret, of a cross bar pivoted tosaid turret, a vertical telescope carried by the cross-bar andprojecting downward into the turret, a reflector carried by saidtelescope, a reflector carried by the cross-bar at its opposite end fromthe telescope, and means for adjusting the angle of the latterreflector, substantially as set forth.

6. The combination with a revolving turret, of a cross-bar pivoted tosaid turret, a vertical telescope carried by the cross-bar and project=ing downward into the turret, a reflector carried by said telescope, areflector carried by the crossbar at its opposite end from thetelescope, and a lever connected to the pivot of the latter reflectorbymeans of which its angle may be adjusted, substantially as set forth.

7. The combination with a revolving turret, of a cross-bar pivoted tosaid turret, avertical telescope carried by the cross-bar and projectingdownward into the turret, a reflector carried by said telescope, areflector carried by the cross-bar at its opposite end from thetelescope, a lever connected to the pivot of the latter reflector bymeans of which its angle may be adjusted, and an adj usting-levercooperating with the said lever for adjusting the position of thelatter, substantially as set forth.

8. The combination with a revolving turret, of a cross-bar pivoted tosaid turret, a vertical telescope carried by the cross-bar andprojecting downward into the turret, a reflector car- IIO ried by saidtelescope, a reflector carried by the cross-bar at its opposite end fromthe telescope, a lever connected to the pivot of the latter reflector bymeans of which its angle may be adjusted, an adj usting-levercooperating with said lever for adjusting the position of the latter,and an adjusting-screw for adjusting the position of theadjusting-lever, substantially as set forth.

9. In a range-finder, an observingtelescope movable relatively to afixed pivot, with the eyepiece of the telescope in approximately theline of said pivot, whereby the adjustment of the telescope to maintainan object in the field of view does not effect a relative movement ofthe eyepiece, substantially as and for the purposes set forth.

This specification signed and witnessed this 22d day of June, 1900.

BRADLEY ALLAN FISKE.

Witnesses:

FRANK L. DYER, JNo. R. TAYLOR.

